Massachusetts gas explosion injures 18; cause under investigation

November 24, 2012 12:00:00 AM PST

SPRINGFIELD, Mass. --

A natural gas explosion ripped apart a strip club and heavily damaged a dozen other buildings in Massachusetts.

The blast Friday night blew out windows in a three-block radius, leaving at least three buildings irreparably damaged. Eighteen people were injured, many of them first responders. No one was killed. None of the injuries were considered life-threatening.

Pieces of broken glass littered streets and sidewalks. It was unclear how many residents had been evacuated. A shelter was set up at a school.

The center of the explosion was cordoned off Saturday morning as inspectors worked to identify unsafe structures.